Carbureter.



J. M. ULRICH 6% W. RAKE, JR GARBURETEE APPLIGATIOH FILED AUG. 2-1, 10x0 1,081 ,Qfig, Patented. 1360.9, 913.

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J. M". ULRICH & W. KAI-1R JR,

UARBURETER.

APELIOATION FILED AUG. 27, 1910.

Patentefl Dec. 9, 1913.

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unirnn marine PATENT onrion.

il 'll'ftillflh M. ULRIUH AND WILLIAM BAKE, 51%., OF MANITOWOO, WISCONSIN; SAID 'llLIEtllUI-llAEESIGNOR T0 SAID RAHB.

Patented Dec. 9, 1913.

Be it known that we, Jennie M. ULnici-r and W'IL IAM Bane, J12, citizens of the United States, residing at Manitowoc, county of Manitowoc, and Fatate of Wisconsin, have invented new and useful Improvernent-s in Carburetors fdr lnteinal-Combud lion Engines, of which the following is .a specification. I

Uur invention relates to improvements in carbureters for internal combustion engines.

Unipresent invention has for its object the provision of meant for producing a similar pulsating pressure upon the liquid and the initial delivery of the liquid through the nozzle in connection with means whereby only a portion of the cylinder air charge is delivered to the mixing chamber past the nozzle, another portion of the air being delivered into the mixing chamber at a, point above the. fuel nozzlc where it is mixed with the charged. air or vapor.

By dividing the air current, we ar enabled to use one portion of it initiallyto aid in spraying and distributing the liquid charge over the walls ot-the itring chamber, We are also able to delay the delivery of the other portion of the air charge and a build up an anterior pressure in the iges sutlicient to produce a forcible he ml discl'iarge at the nozzle, \vl'icrcby the liquid may be thrown and distributed over the upper portion of the Walls of the mixmg chamber, preparatory to the delivery of euch portion of the air charge to the mixing chamber. We secure a delay in the delivery of one portion of the air charge by providing a by-pass lea-ding around that portion of the mixing chamber in which the nozzle is located, to the upper portion of such chamber. and providing a resisting member in this bypass (it such character that an air preesure may be built up in the bypass and directed through-an auxiliary duct upon the surface of the liquid supply to forcibly eject liquid from the nozzle before the pressure is sufficient to overcome the inertiaand friction of the resisting member, said mei'nbcr however, being adapted to move and uncover the connection betv an the lay-pass and the mixing chamber, when v a predetermined pressure. exerted against whereupon a portion ol air passes through in bypass, (illlllll'l' the mporieezl nurture in the mixing chamber and vaporizes the resldual portion of the liquid charge.

In the following, description reference is had to the accompanying drawings in whichge- Figure 1 is a vertical Sectional view showing our improved carbureter, drawn to a plane common lathe-central portions of the mixing chamber and by pass, and also show mg a portion of an engine cylinder in sec- QARBUBETER.

,llnllSllflES rectification of Letters llatent.

' Application filed hugging; p1, 1910. Serial No. 579,324.

To all whom it may concern: 4

tion on a plane extending through the inlet port of the cylinder and the connection of the mixing chamber outlet therewith. Fig. 2 is an elevation of the same as it appears when applied to a two cylinder two cycle englne.

Like parts are identified by the same reference characters throughout the several views. r

In the construction shown a portion of the crank chamber 1 and a portion of the compression chamber 2 of a two cycle engine are illustrated in connection with a carburcter embodying our invention. Admisaion and delivery of air to and from the crank chamber is controlled by a rotary two way plug valve 4, which is provided with a port (3 adapted to register with and connect through the air inletports 8 and 10 of the crank chamber and valve casing or the air outlet port 12 of said chamber and the inlet port 14 of the mixing chamber 16. The air becomes charged with hydrocarbon vapor in the upper-portion of the mixing chamber 16 and is delivered to the compression chamber 2 of the engine through the port 18.

The liquid fuel is delivered to the mixing chamber from. a chamber 20 (preferably a float chamber) through a duct 22 and nozzle :23, the flow of liquid through the latter being in part controlled by the needle valve The mixing chamber is partially/ subdivided below the outlet of the nozzle 23 by a member 26 driven into the lower portion of the mixing chamber or otherwise secured imposition therein having an aperture 28 through which the nozzle 23 extends and which forms an air passage connecting the lower with the upper portion of the mixing chamber. The lower and upper portions'of the mixing chamber are also connected by a by-pass having a vertical portionbO provided with a piston valve 39., which controls the delivery of air through the vertical portion of the bypass into the outlet portion i valve port and the .su'llicient to overcome the inertia and friction thereof, which communicates with the outer portion of the mixing chamber 16. This piston valve 32 is adapted to be lifted by the pressure of air in the by-pass until the air is permitted to escape through the outlet 34 into the mixing chamber. The capacity of the aperture 28 (which is preferably circular in form) is less than the capacity of the ports 12 and ll, these ports having preferably the form of elongated slots. When these ports are open, therefore, a back pressure will be created in the lower part of the mixing chamber be low the member 26 and this pressure will be exerted through the by-pass to lift the pis' h ll 32. The pressure thus developedin the bypass is utilized to force a discharge of the liquid fuel through the duct and nozzle by providing a duct-36 which leads directly from the vertical portion of the bypass into the float chamber 20, thus permitting the air pressure to be exerted upon the surface of the liquid in the said chamber. 'I'his'pressure will exceed the pressure in the upper portion of the mixing chamber 16 above the member 26 and therefore cause a discharge of the liquid through the nozzle 23.

-When the pressure in the by-pass becomes of piston 32, the latter will be lifted to uncoverthe outlet 34. A considerable reduction in the pressure of the air in the bypass will then take place, for the reason that the inertia and friction of the piston will then be'exerted to prevent its downward movement and the outlet 34 is of such capacity as to permit a substantially instant equalization of pressure in the bypass w not necessarythat the'equalization sbou'ld be complete, but it is desirable that it should be sufficiently complete to cause a material reduction in the liquid delivery, if not an entire cessation of such delivery.

\Vith the described construction, whereby the liquid is discharged through the nozzle with considerable'force during the period of maximum pressure,-the 'needle valve 24 may be more nearly closed than in the ordinary ith that in-the mixing chamber. It iscarburetor where the delivery of the liquid depends merely upon the slight suction exerted at the nozzle. It therefore follows that when the reduction in pressure takes place in the .by pass, no appreciable quantity of liquid will pass. through the nozzle, substantially the entire liquid charge having been delivered before the resisting piston 32 can uncover the outlet or port 34. eprefer a weighted piston or plunger to an ordi nary spring actuated valve, for the purpose of providing the necessary resistance to the passage of air through the by pass, for the reason that a weighted piston or plunger is slow in its operation, both in. opening and in closing when compared with the opera- 1 tion'of a spring controlled valve of light weight. The piston 32 does not start promptly, and when in motion, itcontinues in motion until the outlet 3a is quite fully open. In the ordinary operation of a hydrocarbon engine, the piston will not return to cut oil' the outlet opening 32 until the end or nearly the end of the period of air de livery. This permits a greater degree of equalization in pressure during the open period than would be permitted by a spring actuated valve. A duct L0 communicates between the upper portion of theinixing chamber 16 and the space 42 above the piston 32. A. ball valve. 4% obstructs the flow of air or apor through this duct to the mixing chan'iber and thus permits an air cushion to form above the piston valve 32 but allows air to enter the space above this piston valve from the mixing chamber when the valve descends. purpose ofcushioning the piston valve and of permitting it to descend freely after the delivery of the air charge to the mixing chamber. 4

A screw threaded member 46 isadjustably mounted in the casing above the ball valve ll, whereby the movement of said ball is limited. This feature of our construction, involving the duct 40 and valve 44;,"is1of especial importance where a throttle valve, such valve 48, is employed to regulate the speed of the engine by controlling the delivery of vapor through the port 18. These valves are located, in accordance with ordinary practice, at the inlet to the engine cylinder, vi. 0., the outlet of the carburetor, and in the construction illustrated thcyare locatedl'ieyond the connection of the duct .40 with the mixing chamber. lVhen the throttle valve is partially closed, considerable pressure may be developedin the mixing chamber and by pass .30, if air under pressure is being deli vercd through the inlet port 14. The by pass, however, permits the air or vapor to pass from the mixing chamber to the space above the piston 32, thus permitting piston to descend, since the pressure above valve 32 cannot fall materially below the pressure in the mixing chamber.

It will be understood that the valve 48 is an oscillatory valve operated manually. When an engine is governed in the usual manner the rotary plug valve 4: may also be actuated from the engine in any ordinary manner, the means for operating such valves being wellunderstood and, therefore, not illustrated herein. It will also be understood that the float 50 in float chamber operates in the ordinary manner through a lever 51, and valve .32 to control the delivery of liquid to the float chamber from any suitable source of supply through'the' inlet duct 54.

lVhere a single carburetor is employed in an engine having more than one cylinder and piston, a rotary valve 4: will be em ploycd for each cylinder, and the inlet ports of the mixing chamber will contact with passages 56 leading to the lower portion of the mixing chamber. The upper portion of the mixing chamber will be similarly connected by outwardly extending passages 58 with the cylinder ports 18. Where this is done the; duct .10 will preferably be connected with the passagentl at one or both sides of the mixing chamber 16.

While'we have shown and described our invention as applied to a two cycle engine, we do not limit the scope of our claimn to the combination with such an engine, since it'is obvious that it is a plicable to any form of engine where a dill' c rence is secured be tween the pressure in the mixing chamber at the point of fuel delivery and that of the air before it reaches such point. In an ordinary two cycle engine this difference is created by compression .n the cranlr chamher, while in a four cycle engine it is secured by the partial vacuum developed in the mix ing chamber during the suction stroke of the engine piston, by applying an in tial air pressure to the surface of the liquid in excessof the pressure at the nozzle, and forci ble delivery of the liquid fuel is thus secured, and this delivery being initial, it obvious that the delivered fuel Will be exposed to all the air passing through the aperture :28 and the fuel thereby etticctuall vaporized. The delivery of the liquid t rough the nozzle being a forcible delivery, produced virtually by an impact pressure of air in the float chamber, it is obvious that such liquid delivery is not materially affected by relative density ;-at least the delivery of such liquid will not be affected by a variation in density greater than the increase or decrease of the fuel value of the liquid due to th variation in density; it would also be observed that the delivery of the liquid fuel is not dependent upon the height of the liquid in the float chamber, there being practically no difference in the quantity delivered, Whether float chamber is nearly full or nearly empty. We regard the use of the rotary valve 4 or its equivalent as very important for the purpose of timing the pres sure impulse upon o fuel and developing a considerable degree-of kmetic energy in the air entering the float chamber. This can-- ables us tovirtually secure What We call a hammer pressure upon the liquid fuel which ejects it under the influence of shock. T his hammer pressure is due to the iii-rush of air when valve 4; opens, and is similar in effect to. that secured in a hydraulic ram, although the force is greatly diminished by reason of the elastic character of the fluid, which diminishes the shock. The rcsult is, however, that quick and positive jet fof liquid fuel is delivered; This i true Whether the carburetor is employed for a two cycle or for a four cycle engine, since the valve at may allow av vacuum to build up in all parts of the mixing chamber before opening to atmospheric air, and therefore the opening of said valve provides for a sudden rush of air through the carbureter either from the atnu'isphcrc, or from a compression chamber in case the carburetor is used in connection with a two cycle engine and air under pres sure delivered without reducing the pressure in the mixing chamber materially belou atmospheric ressurc.

having t ms described our invention What we claim as new and desire to secure by Letters Patent is l. A carburetor for internal combustion engines comprising the combination with a uniting chamber provided with a valved air inlet, a vapor outlet and a fuel inlet at an intermediate point, of an obstruction in said chamber, located between the air and fuel inlets and adapted to direct a portion of the air to the fuel entering through the fuel inlet, a by pass leading around said obstruction, a fuel supply chamber provided with an outlet communicating with the fuel inlet of the mixing chambei, and also having an open connection between lls upper portion yielding obstruction and the by pass, and a said open COIlllGCtlull in said by pass between with the fuel chamber, and the point of air delivery to the mixing chamber beyond the obstruction therein, together with a noeterior throttle controlling the delivery of the mixture through the outlet.

2. A. carbureter for internal combustion engines, comprising the combination with a mixing chamber provided with a valved air inlet, a vapor outlet and a fuel inlet, of a by pass connecting the inlet and outlet por tions of the mixing chamber, around the portion occupied by the fuel inlet, means for restricting the pas-2 igo of air through that port ion of the mixing chamber occupied by the fuel inlet, a yielding ol'istruction to the passage of air through the by pass, and means for utilizing the air in the by pass in advance of said obstruction, to develo) a )rcssurc upon the fuel in advance of the fuel inlet. together with a posterior throttle controlling th delivery of the mixture through the outlet. 3. A carburetor for internal combustion engines, comprising the combination with a mixing chamber provided with a valved air inlet, a vapor outlet and a fuel inlet, of a by pass connecting the inlet and outlet poi tions of the mixing chamber, around the portion occupied by the fuel inlet, means for restricting the passage of air through that portion of the mining chamber occupied by the fuel inlet, a yieldin obstruction to the passage of air throng the by pass and means for utilizing the air in the by pass in advance of said obstruction, to develop a pressure upon the fuel in advance of the fuel inlet, sa'dmeans comprising a fuel chamber having its lower portion in communication with the fuel inlet and its upper portion in communication with said by pass, together with a posterior throttle controlling the delivery of the mixture through the outlet.

4. A carburetor for internal combustion engines, comprising the combination with a mixing chamber provided with a valved air inlet, a vapor outlet and a fuel inlet, of a by pass connecting the inlet and outlet por- 'tions of the mixing chamber, around the portion occupied by the fuel inlet, means for restricting the passage of air through that portion of the mixiifn; chamber occupied by the fuel inlet, a yielding obstruction to the passage of air through the by pass and means for utilizing the air in the by pass in advance of said obstruction, to develop a pressure upon the fuel in advance of the fuel inlet, said means comprising a fuel chamber having its lower portion in communication with the fuel inlet and its upper portion in communication with said by pass, and said yielding obstruction comprising an automatically closing valve, located in the by pass and adapted to be actuated to. open position by the pressure of airthereon, to gether with a posterior throttle controlling the delivery of the mixture through the outlet.

A carburetor for internal combustion engines, comprising the combination with a fuel supplychamber, a mixing chamber pro vided with a valved air inlet, a vapor outlet, and an intermediatefuel inlet of a by pass connecting the air inlet and the outlet portions of said chamber around the portion occupied by the fuel inlet, means for restricti ing the passage of air past the fuel inlet, an

automatically closing valve in the by pass, a duct connecting the by pass in advance of said valve with the upper portion of the fuel chamber, and a duct connecting the lower portion of the fuel chamber with the fuel in let, said valve being adapted to open under a predetermined pressure in the by pass, to 'ether with a posterior throttle controlling the delivery of the mixture through the outlet.

ing a portion of the connecting the air inlet and the outlet portions of said chamber around the portion occupied by the fuel inlet, means for restrict-- ing the passage of air past the fuel inlet, an automatically closing valve in the by pass, a duct connecting the by pass in advance of said valve wit the upper portion of the fuel chaniberand a duct connectii'ig the lower portion of the fuel chamber with the fuel inlet, said valve being adapted to open under a predetermined pressure in the by pass and having the space back of the valve connected by an auxiliary duct with the mixing chamber.

7. A carburetor for internal combustion engines, comprising the combination with a fuel supply chamber, a mixing chamber provided with a valved air inlet, a vapor outlet, and an intermediate fuel inlet, of a by pass connecting the air inlet and the outlet portions of said chamber around the portion occupied by the fuel inlet, means for restrictmg the passage of air past the fuel inlet, an automatically closing valve in the by pass, a duct conncctiiw the by pass in advance of said valve with the upper portion of the fuel chamber and a duct connecting the lower portion of the fuel chamber with the fuel.

inlet, said valve comprising a piston valve provided with an auxiliary valved passage communicating between the mixing chamber and the space back of the piston valve, to admit air to such space sulliciently to permit the valve to close after it has been opene by the pICSSUIG in the receiving portion of the by pass.

8. A carburetor for internal combustion engines, comprising the combination of a mixing cl'iamber provided with a valved air inlet, a fuel inlet and a vapor outlet, of means for mechanically developing pressure in the air delivered to the anterior portion of. the mixing chamber, means for temporarily applying said pressure advance of the fuel inlet, means for directair past the fuel inlet, means for deliverin another portion of said air to the mixing c amber beyond the fuel inlet, and a throttle valve controlling the vapor outlet.

In testimony whereof We affix our sigma-- tures in the presence of two witnesses.

JULIUS M. ULRICH. WILLIAM RAHR, JR.

Witnesses LEVERE'IT -C. NVE'EELER, G. J. DAVELAAR.

to the fuel in I 

